<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<script src="../js/vue.js"></script>
	</head>
	<body>
		<div id="root">
			<!-- 随绑定的数据变化而变化 -->
			<h1>{{username}}</h1>
			<!-- 只进行一次插入，后续不会改变 -->
			<h2 v-once>{{username}}</h2>
		</div>
		
		<script type="text/javascript">
			new Vue({
				el: '#root',
				data: {
					username: '张三'
				}
			})
		</script>
	</body>
</html>